Keyboard encoder with plural and different sets of code members



Feb. 7, 1967 J. E. HICKERSON KEYBOARD ENCODER WITH PLURAL AND DIFFERENT SETS OF CODE MEMBERS Filed July 29, 1965 3 Sheets-Sheet 1 ATTORNEY.

J" E. HICKERSON Feb. 7, 1967 KEYBOARD ENCODER WITH PLURAL AND DIFFERENT SETS OF CODE MEMBERS 3 Sheets-Sheet 2 Filed July 29, 1965 Feb. 7, 1967 J. E. HICKERSON KEYBOARD ENGODER WITH PLURAL AND DIFFERENT SETS 0F CODE MEMBERS Filed July 29, 1965 3 Sheets-Sheet 5 United States Patent 3,302,764 KEYBOARD ENCGDER WITH PLURAIL AND DHFFERENT SET 0F CGDE MEliilBERS John E. li-liickerson, Lexington, Ky., assignor to internationai Business Machines Corporation, Armonlk, N.Y.,

a corporation of New York Filed .lluly 29, 1965, Ser. No. d75,68ll 4 Claims. (Cl. 197-16) This invention provides an encoding keyboard having a limited number of key'buttons for generating a large number of different coded items greatly in excess of the number of keybuttons.

Single element or character matrix printers employ mechanisms responsive to a mark-spaced" code for locating the individual characters of the matrix to be printed. A small number of characters can be located along a single coordinate in the case of a type wheel. It is more practical to locate larger number of characters along dual coordinates as in the case of cylindrical, spherical, or mushroom shaped matrices. Thus, it is understood that a major component of a single element printer is the converter for transforming mark-space coded coordinate data into analog coordinate displacement for positioning the character matrix.

The prior art contains a multitude of varied code-toanalog converters for this purpose. It is thus not difficult to find some conversion mechanism; rather, the problem lies in finding a mechanism that can operate at adequate speed while reliably and continuously providing precision output for a satisfactorily long useful life; be manufacturable at a reasonable cost, and occupy a minimum of space. All of the foregoing practical necessities rapidly become more difiicult to attain as the number of characters on a matrix is increased.

With the ever expanding use of data processing and data communications equipment, the associated need for more available characters and symbols has resulted in a proposed standard code known as the ASCII or X3.4 code. This code includes seven information bits or channels which inherently provide for 128 pieces of information such as characters, symbols, or machine functions. Some 90 odd codes are presently assigned to characters. The ASCII Code is characterized by the absence of conventional shift codes of the type employed in the Bedot or Teletypewriter standard code. Thus, each character or function is totally identified by a single seven bit code. The practical problems enumerated above are thus further aggravated due to the lack of intermediate shift codes which otherwise would reduce the printing matrix travel. A printer constructed to operate on the ASCII Code will, by definition, have some input-output ability such as reading and/or punching paper tape. However, it is desirable to also provide a keyboard for manual data entry.

A practical keyboard for ordinary rapid stenographic use is limited by operator considerations to a maximum of to keybuttons. Conventional typewriters and teletypewriters employ keyboards having shift keys which ordinarily do not modify the action of the keyboard, but shift a type basket or type matrix of the printing mecha nism to present a different character in response to substantially the same mechanical action from the keyboard. When conventional typewriters and teletypewriters are used in an input-output context, they employ shift codes to duplicate the keyboard action. A printer that is constructed to operate internally on a code set lacking shift code must receive data from its keyboard in the same form. It is thus necessary to provide multiple mechanical outputs from each individual key button.

An important object of this invention has been to provide an improved keyboard for producing multiple coded 33%,764 Patented lFeh. 7, i967 outputs from each key button to permit the generation of a full code set lacking shift codes from a limited number of key buttons. This and other important objects of my invention will appear to those skilled in the art from the following description of the novel concepts employed and a specific embodiment thereof.

A principal concept of this invention relates to a keyboard structure which is basically like that disclosed in my prior Patent No. 2,978,086, Key Operated Machines, issued April 4, 1961. The keyboard therein described produced only one coded output for each keybutton. However, between two and three times as many output codes are required as key buttons are permitted. By this invention the limited number of available key buttons are combined with shift keys that vary the output of the key buttons, not the structure of the printer. Each key button is thus capable of producing different coded outputs, depending upon the keyboard shift status, but the printer recognizes all codes alike and does not respond to keyboard shift as such. Keyboard shift is accomplished in this invention by the provision of three sets of encoding slides, each of which functions substantially as disclosed in my earlier patent. Only one set of encoding slides is operative at any given time, the various sets being selected by three interposers that each block movement of two sets of slides and permit movement of a third set. The shift interposers are controlled by three shift key buttons which operate to permit the storage of one shift status and release of the other as selected by the operator. The keyboard of this invention can be connected either mechanically or electrically to the selector mechanism, which is the subject of co-pending US. patent application Serial Number 475,687 entitled Character Selection for Single Element Printing Mechanisms filed in the names of John E. Hickerson and Henry R. Kruspe. The significant factor in the connection is the direct relationship between movement of each encoding slide with an associated cam control clutch.

The foregoing and other concepts of this invention can be understood in greater depth from the following description of a specific preferred embodiment of the invention wherein particular reference is made to the accompanying drawings of which:

FIGURE 1 is a front perspective view of a code-toanalog converter or selector schematically connected with a typical character matrix for purposes of illustration;

FIGURE 2 is an enlarged exploded perspective view of a cam mechanism shown in FliGURE 1;

FIGURE 3 is a front perspective view of a portion of the keyboard constructed in accordance with this invention;

FIGURE 4 is a circuit diagram showing a preferred wiring arrangement for interconnecting the keyboard of FIGURE 3 with the selector mechanism of FIGURE 1; and

FIGURE 5 is a circuit diagram showing a modified clutch control circuit for producing a no-restore home or direct ChZliElCitil lO-Ciltlffltllfil selection control of the elector shown in FIGURE 1.

Referring more specifically to the drawings in FIGURE 1, there is shown a printer or typewriter T having a print head or character matrix 16 similar to that disclosed in U.S. Patent 3,247,941 entitled, Printing Head With Means to Position Head Before Striking Movement Begins, of H. S. Beattie and I. E. Hickerson, filed December 20, 1963. The print head it) is displaced vertically along a coordinate axis 1 .in character space increments 12 as shown schematically by pulley 13 and is rotated along a coordinate axis 14 as shown schematically by a pulley .15. For simplicity, the print head it is shown as being stationary and cooperating with a moving platen 16, al-

though it will be understood that the print head could be mounted on a movable carrier as disclosed in my aforesaid U.S. Patent 2,978,086.

The vertical displacement pulley 13 is positioned by spring loaded parallelogram mechanism including end levers 21 pivoted about respective axes 22 and carrying pulleys 23 which operate closed loop tape 24. The tape 24 is operatively connected to and wrapped around pulley 13 whereby pivotal displacement of end levers 21 will transmit motion through the tape 24 to the pulley 13. The end levers 21 are interconnected by complementary drive bar 25 such that both will be positively driven an equiangular amount.

The drive bar 25 is provided with detent or homing notches 26 corresponding to each of its possible character selecting positions. A cam-operated detent pin or tooth 27 engages a notch 26 after the selection portion of each print cycle to positively locate the parallelogram mechanism 20 in an exact print character location. It will be noted that the above-mentioned US. Patent No. 3,247,041 disclosed detenting means within the print head itself. It is preferred to provide both the print head detenting means and the selector detenting means as shown herein to divide the total detenting function and thereby minimize the amount of detenting force required within the print head where space and weight are at a premium.

A parallelogram mechanism 30, similar in structure and operation to mechanism 20, is provided for controlling the rotate control pulley 15 and does not require a detailed description.

It will be understood that the combined position of the mechanisms 20 and 30 as transmitted to pulleys 13 and 15 will select a single character position on the matrix of print head 10. The mechanism for driving the print head 10 against the platen 16 is not part of this invention. An appropriate driving mechanism is disclosed in U.S. Patent 2,919,002 entitled, Selection Mechanism for a Single Printing Element Typewriter, issued to L. E. Palmer, December 29, 1959.

The mechanism for positioning parallelograms 20 and 30, and hence matrix 10, comprises a pair of preferably coaxial code-to-analog converters or selectors and which produce an analog output in the form of variable axial length that is transmitted to the parallelograms 20 and 30, respectively, through sliding sleeves 28 and 3i. Selector 40 comprises three cooperating face cam pairs 41, the individual construction of which is best shown in FIGURE 2.

Each face cam pair 41 comprises a contour cam 42 and a follower cam 43, both supported on a stationary shaft 44 having a central axis d5. Contour cam 42 is permitted to rotate and slide axially along the shaft 44. Follower cam 3 engages a keyway 45a and is thus permitted to slide axially only along the shaft 45. The follower cam 43 of the left-most pair 41 in selector 40 is securely mounted on a base plate to that can be part of the stationary printer frame. The contour cam 42 has a camming face 47 including a high dwell portion 47a and a low dwell portion 471) spaced apart by predetermined angle 06 and connected by smooth transition or rise portions 47c. The high and low dwell portions are separated by a distance d. which is proportional to the spacing between characters on the matrix l0. Preferably, the distance d varies between cam pairs 41 in a binary progression. For example, the distance d of one cam pair 41 is proportional to one unit 12 of vertical displacement of the print head 10; another is proportional to two units of displacement; another is proportional to four units of the vertical displacement. The follower cam 43 of each pair 41 has a camming face 48 including a follower projection 48a having a rise portion 48]) that is greater in axial extent than the distance d of its associated contour cam 42.

Contour cams 42 are selectively rotated by individual control mechanisms connected thereto through intrically formed gear or splined portions 61 by respective control character in coded form.

pinions 62. The lengths of the spline portion 61 is selected to permit engagement with its control pinions 62 in any of the translated or axially moved positions of the associated contour cam 42. The control pinions 62 are mounted on a continuously rotating shaft 63 driven by pulley 64 and a suitable motor, not shown. Each pinion 62 includes a selectively operable one revolution cyclic cltuch having a pawl 65 and ratchet 66 which are normally held out of engagement by a latch 67 that is operated in response to an electromagnet or other control means 68. The gear ratio between the pinion 62 and the gear 61 is chosen to be 1:1, such that each operation of the electromagnet 68 will produce a complete revolution of the face cam 41.

From the foregoing it will be understood that matrix 10 is positionable along axis 11 from zero to seven characters location increments by operation of selected control means 60. Rotational incrementing is obtained by selector mechanism 50 which is basically similar to selector mechanism :0 described above, and includes a plurality of face ca m pairs 51 constructed basically the same as the pairs 41 described in detail above. Two separate face cam pairs 52 are employed, however, to obtain eight units of movement by having increment distances (1 (FIGURE 2) of four units each. Both of the contour cams in pairs 52 rotate simultaneously upon operation of the associated control means 60. The remaining cam pairs 51 are operated individually by their respective control means 60. The selector 50 is thus capable of lateral displacement correlative to any of 0 to 15 units of rotational character displacement of the print head 10.

In FIGURE 3 a keyboard K is shown that is similar in basic structure and operation to that disclosed in aforesaid U.S. Patent 2,978,086. As fully described therein, depression of a key button 71 actuates a character representing sword or stop member 72 by releasing it from a latch 73 to move downwardly under the influence of a spring 74 and pierce a stack of coded slides 75 or thin strips. The sword 72 also strikes bail 81 rotating it clockwise to close a cycle switch S2. Bail 81 further operates latch 33 to release spring biased arm 84 to move to the left of FIGURE 3 and permit slides 75 to move from a normally inactive position leftwardly under the influence of appropriate springs 76 to an active position. The coding in the slides 75 takes the form of long and short slots or openings 77 which cooperate with the selected sword 72 to permit only selected slides 75 to move to the left, thus representing the desired Electromagnets 85 and 86, respectively, restore the spring biased arm 84 and ball 81 to permit the selection of a second key button. The slides 75 which are permitted to move leftward close switches 78 which are individually associated therewith. As hereinafter explained in connection with FIGURE 4, closure of the slide controlled switches '78 activates respective control means 60 (FIGURES 1 and 2) to select a cycle of operation of the various face cam pairs to produce a character selection for printing.

The keyboard K shown in FIGURE 3 differs from that of U.S. Patent 2,978,086 in that the stack of slides 75 actually includes three separate groups of code slides 91, 92 and 93 that operate alternatively to control the switches 78 in response to key button selection in cornbination with a shift status selection by shift keys 94, and 26. The slides in each group 91, 92 and 93 are coded differently, as required, to produce three different coded outputs from each of the key buttons 71, thus permitting a practical number (between 40 and 45) of key buttons 71 to select between a large number of coded items.

The shift status selecting mechanism comprises the three shift keys 94, 95 and 96 which position, when depressed, an associated selecting finger or interposer 94a, 95a or 96a into respective coded openings 97 whereby one group 91, 92 or 93 of slides will be permitted to move under r control of sword 72 while the other two groups are inhibited. Latches 94b, 95b and 96b cooperate with respective shoulders 94c, 95c and 96c to hold a selected shift key in its depressed position and are interconnected by a bail 98 to release a previously selected shift key from its depressed position, such that only a single shift key will be held depressed at any one time. The keyboard K is operated by first depressing any of the shift keys 94, 9S and 96, thus selecting one of the groups of encoding slides 91, 92 and 93 and subsequently depressing a key button 71 to generate a coded representation of the selected data item at the switches 78 according to the particular keyboard case selected.

FIGURE 4 shows suitable circuitry for interconnecting the keyboard of FIGURE 3 to the selector mechanism of FIGURE 1, and also shows mechanism by which the selectors 40 and 50 of FIGURE 1 can be controlled directly by a source of coded data such as a paper tape reader R of conventional construction. In FIGURE 4 it will be seen that each of the pinions 62 of control means 60 are operated by respective electromagnets 68 controlled, in part, by slide operated switches 78.

Control means 60 are also operable from the tape reader R which closes internal switches (not shown) in response to sensing holes in the perforated tape. Cycling of the printer T is controlled by an electromagnet C to perform all the various cycl c functions as described in US. Patent 2,978,086 in a sequential timed relation. Operation of magnet C is controlled either by cycle switch 82 in the case of key-board operation, or directly from the reader R as a function of reader cycle time. Preferably, the keyboard K is made ineffective to control the electromagnets 68 during a reader operation by a gang switching means R which is operative by electromagnet R at all times during reader operation.

The print cycle mechanism controlled by electromagnet C performs many print functions not shown and also drives cycle earns 87 and 88 which close individual switches to respectively restore the encoding slides 75 and terminate the cycle by operation of electromagnets 85 and 86.

The pinions 62 are permitted to rotate a complete revolution upon each operation of their associated clutch, thus driving their associated contour cams 42 a complete revolution passing through the high dwell :portion 47a on the wav. Accordingly, with the mechanism as shown in FIGURE 4, the print head 10 will restore to a home position after each print cycle. It is desirable to have the print head move directly between various characters rather than return home. Direct selection permits the print operation to occur later in the print cycle as no time need be alloted to the restoration of the print head to its home position. In FIGURE there is shown a modified control means 100 which permits the print head to remain in its selected position and go directly between character selections, rather than through a home position. The mechanism shown includes a typical cam drive gear or splined portion 101 like 61 of FIGURE 2 and a control pinion 102 having a 1:1 ratio with the gear 101. This mechanism differs from that of FIGURE 2 by employing a /2 revolution or 180 clutch 103 in place of the full revolution clutches disclosed above. The clutch 103 is of. known construction, for example, a similar clutch is disclosed in US. Patent 2,919,002 mentioned above. Clutch 103 is controlled by a spring-biased latch 104 which is actuatable by compound electromagnet 111. A feedback or position indicative pin 105 is carried :by the pinion 102 and is positionable either as shown, or 180 displaced therefrom as the pinion 102 is displaced in 180 increments. When the feedback pin 105 is displaced 180 from the position shown in FIGURE 5, it operates intelligence data switch 112 to its closed operating state, thus indicating that the pinion 102 is in its actuated position.

The compound magnet 111 includes a core 113, a first coil or winding 114, and a second coil or winding 115. The coils 114 and 115 are wound about the core 113 in opposite directions to produce opposite polarity when energized. Accordingly, operation of either coil alone will actuate the latch 104, Whereas simultaneous actuation of both coils 114 and 115 will cancel any overall magnetic effect to prevent actuation of the latch 104. A pair of print cycle controlled switches 116 and 117 determine the point in the print cycle during which the control mechanism will be operated. Control of the circuit is by a typical slide controlled switch 78, like those shown in FIGURES 3 and 4, which produces either of two characteristically different signal inputs, i.e., open or closed.

Operation of the circuit shown in FIGURE 5 is as follows. With the mechanism in the position shown wherein reference arrow 106 points upward, closure of the switch '78 in response to keyboard selection of a code requiring a bit represented by control means 100, energizes the circuit including coil 114 when the cycle switch 116 is closed. Coil 115 is not energized because switch 112 is open. Latch 104 is picked temporarily as controlled by cycle cam 116 and permits a /2 revolution of the control pinion 102. Rotation of the pinion 102 rotates the cam drive gear 101 to position its associated cam in its high dwell or active position and reference arrow 106 will point downward. Upon selection of the next character, switch 78 will either be closed or not closed, depending upon the coding of the character selected. Assuming that the switch 78 is closed, thus again calling for the active (or arrow 106 down) position of the cam associated with drive gear 101, coil 114 will be energized as before upon closure of the cycle switch 116. However, pin will have closed switch 112 and coil will also be energized upon closure of cycle switch 117 to negate the overall magnetic: flux of the compound magnet 111. Accordingly, the latch 104 will not be picked and the pinion 101 will remain in its active (arrow 106 down) position. Assuming, on the other hand, that the second selected code did not call for closure of switch 78, proper selection would require the return of pinion 102 and cam drive gear 101 to their home (arrow 106 up) positions. Switch 78, remaining open, would not energize coil 114 upon closure of cycle switch 116. However, switch 112, being closed by feedback pin 105, would energize coil 115 upon closure of cycle switches 116 and 117 to momentarily pick the latch 104, thereby permitting a rotation of the control pinion 102 to its home position.

Those skilled in the art will fully understand and appreciate that this invention provides a keyboard capable of generating a number of different codes greatly in ex cess of the number of keybuttons by the simple provision of a plurality of alternatively operable encoding slides. While a specific embodiment has been shown for purposes of illustration, it will be understood that various modifi cations and additions can be made to the disclosed mechanism without departing from the novel concepts and spirit of this invention which are limited only by the appended claims.

I claim:

1. A key operated machine comprising, in combination,

a plurality of keybuttons operable manually for causing different machine functions,

a stop member operatively associated with each of said keybuttons for actuation thereby,

a first plurality of operatively adjacent slides, each individually longitudinally movable between active and inactive positions,

a second plurality of operatively adjacent slides, each individually longitudinally movable between active and inactive positions and positioned operatively adjacent said first plurality of slides,

openings in all of said slides in each plurality in align- 4 ment with each other at points opposite said stop members when said slides are in their inactive positions, said openings adapted to receive said stop members when actuated and being of such lengths that each of said slides is either held against move- ".ent by a stop member or is permitted to move to its active position,

means yieldingly urging said slides toward their active positions,

means releasably holding said slides in their inactive positions,

means operating on actuation of any one of said stop members for releasing said holding means,

means operating in response to movement of said slide to active positions for producing a function representative of the keybutton actuated, and

manually controllable means for conditioning said first and second plurality of slides for response to said keybuttons by selectively, alternately, positively in hibiting longitudinal movement of said first plurality of slides and permitting movement of said second plurality and vice versa.

2. A key operated machine as defined in claim 1 where- 3. A key operated machine as defined in claim 1 wherein said inhibiting means comprise a pair of shift keys, latch means interconnecting the operation of said shift keys whereby a shift key when depressed will be retained in its depressed position and the other shift key, if previously depressed, will be released from its depressed position,

a pair of individual interposers operatively connected to said shift keys for movement to an active position upon depression of their associated shift keys and openings formed in said first and second pluralities of slides for receiving said interposers, and said openings being of such length that the slides in one plurality are either held as a group by an interposer or permitted to move.

4-. A key operated machine as defined in claim 1 wherein said function producing means comprises a plurality of electrical switches for generating a mark space code signal representative of the key button actuated.

References Cited by the Examiner UNITED STATES PATENTS 487,981 12/1892 Buckingham 197--34 X 1,974,307 9/1934 Griffith 197-17 1,983,943 1/1935 Grifiith 197 17 2,559,637 7/1951 Kirchel 19717 2,919,002 12/1959 Palmer 197-16 2,938,952 5/1960 Roggenstein ]97l7 2,978,086 4/1961 Hickerson l97l6 3,014,569 12/1961 Palmer 197l6 3,057,210 10/1962 Stoddard 74-1 3,135,371 6/1964 Young l9716 3,227,259 1/1966 Howard 197-49 ROBERT E. PULFREY, Primary Exmniner.

E. S. BURR, Assistant Examiner. 

1. A KEY OPERATED MACHINE COMPRISING, IN COMBINATION, A PLURALITY OF KEYBUTTONS OPERABLE MANUALLY FOR CAUSING DIFFERENT MACHINE FUNCTIONS, A STOP MEMBER OPERATIVELY ASSOCIATED WITH EACH OF SAID KEYBUTTONS FOR ACTUATION THEREBY, A FIRST PLURALITY OF OPERATIVELY ADJACENT SLIDES, EACH INDIVIDUALLY LONGITUDINALLY MOVABLE BETWEEN ACTIVE AND INACTIVE POSITIONS, A SECOND PLURALITY OF OPERATIVELY ADJACENT SLIDES, EACH INDIVIDUALLY LONGITUDINALLY MOVABLE BETWEEN ACTIVE AND INACTIVE POSITIONS AND POSITIONED OPERATIVELY ADJACENT SAID FIRST PLURALITY OF SLIDES, OPENINGS IN ALL OF SAID SLIDES IN EACH PLURALITY IN ALIGNMENT WITH EACH OTHER AT POINTS OPPOSITE SAID STOP MEMBERS WHEN SAID SLIDES ARE IN THEIR INACTIVE POSITIONS, SAID OPENINGS ADAPTED TO RECEIVE SAID STOP MEMBERS WHEN ACTUATED AND BEING OF SUCH LENGTHS THAT EACH OF SAID SLIDES IS EITHER HELD AGAINST MOVEMENT BY A STOP MEMBER OR IS PERMITTED TO MOVE TO ITS ACTIVE POSITION, MEANS YIELDINGLY URGING SAID SLIDES TOWARD THEIR ACTIVE POSITIONS, MEANS RELEASABLY HOLDING SAID SLIDES IN THEIR INACTIVE POSITIONS, MEANS OPERATING ON ACTUATION OF ANY ONE OF SAID STOP MEMBERS FOR RELEASING SAID HOLDING MEANS, MEANS OPERATING IN RESPONSE TO MOVEMENT OF SAID SLIDES TO ACTIVE POSITIONS FOR PRODUCING A FUNCTION REPRESENTATIVE OF THE KEYBUTTON ACTUATED, AND MANUALLY CONTROLLABLE MEANS FOR CONDITIONING SAID FIRST AND SECOND PLURALITY OF SLIDES FOR RESPONSE TO SAID KEYBUTTONS BY SELECTIVELY, ALTERNATELY, POSITIVELY INHIBITING LONGITUDINAL MOVEMENT OF SAID FIRST PLURALITY OF SLIDES AND PERMITTING MOVEMENT OF SAID SECOND PLURALITY AND VICE VERSA. 